Arlo and Janis by Jimmy Johnson for December 13, 2014

Winter Solstice is December 21st. Has the shortest time of daylight of all the days of the year. Vampires love Winter Solstice.

But Arlo is talking about true solar noon… the moment the sun is at its highest point of the day.It fools people who pay really close attention to sunset time, into thinking the days are already getting longer…

Solar noon varies day by day, due to the Earth’s tilt, and according to latitude, so it’s not necessarily when our clocks say noon.

The length of the daylight gets shorter as the solstice approaches…but solar noon, in the middle of those hours, moves a few minutes later each day…

Tiny differences, but depending upon where you live, you have probably already seen, or are about to see, the earliest sunset of the year.Tomorrow the sun will probably rise a minute later, but then not set until a few moments later than it did today… because solar noon will also be a minute later.

So you’ll actually have some total seconds less of daylight…. but the CLOCK TIME of the sunrise and sunset might actually be a minute later.

Ok I just looked…. so as an example…where I am, by the solstice, the sun will already be rising four minutes later and setting two minutes later than it did today…

and then the actual daylight hours will start to lengthen too.

(And somebody said I wasn’t a nerd…. sigh….)

I’m in northernmost Maine with an almost 180 degree view of the western skyline. It amazes me just how far south the sun has moved and how many hours of daylight we’ve lost since June. With Winter now setting in I’m just glad to see the Sun at all….even just a glimpse.

I am suspicious of the sun and its purported location relative to earth. I often drive Atlanta to Charlotte at dawn and am stricken to see the sun rising to my left. God is trying to confuse me.

@SusanSunshine & Arlo: I didn’t know that!

At 40° North, the sun set the earliest Dec 7th. About Jan 4th will be the latest sunrise.

Cool

I learn something new every day. Thanks, Susan Sunshine

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QuietStorm27: Don’t be too sure about college age. It is probably out of date, but when I was permitted to teach, the average community college student was 38. When I was getting my MS while in my 50s, I was older than all my classmates and all but one of my professors – but neither by much and this was at a state university.

This is really cool. Thank you Arlo and SusanSunshine!

The Navy prints up a book, annually, that gives you the degrees that the sun is above the horizon at high noon on every day of that year. Using this data, one can calculate the degree of latitude that one is at. One’s degree of latitude can also calculated manually, using sines, cosines and stuff like that. There used to be a calculator designed for the sole purpose of accomplishing that. All that went bye-bye with the advent of satellite navigation systems. But I still own an old sextant; it is such a handsome looking instrument.

It’s not a win-win if you get up at 5 a.m.

In my area the change happens Tuesday — the sun sets one minute later and I will dance for joy — I don’t care what happens in the morning because I’m not up for it.

You’re very welcome, anybody who said thanks.

Also…. alongside the eastern edge of the San Francisco Bay, you can be driving north, according to a compass, while according to the highway signs, heading west towards San Francisco on Hwy 80, and east towards Sacramento, on 580…all at once.

And where the eastbound and westbound highways divide, if you want to actually stay on 580 and go north, there’s no clue on the signs whether you should take the east or west direction…all you know is you don’t want to go towards either of those cities.

The first few times I did it, San Francisco sounded more reasonable than Sacramento, so I crossed the wrong bridge and got briefly lost, and took the scenic route home.Took a couple of years to feel pretty sure I had to pretend to be driving to Sacramento for a few miles in order to keep going north to get home to Santa Rosa.

You had to keep to the left of many lanes, and eventually the eastbound traffic would split off to the right…Welllll…. till a night in 1989, when I went to a wedding, after an earthquake, and nobody told me the rebuilt highway included an off ramp on the right for the northbound traffic, and otherwise now kept heading east.

Clear? No, neither were the signs, and neither was I…. for MILES in the wrong direction…. at midnight ….

catman5169: And it is not much better going the opposite way with the sun hitting you by way of your car’s mirrors.

The tilt is related to it, but the biggest reason is due to the elliptical shape of Earth’s orbit around the sun, which causes the length of the solar day to vary slightly throughout the year.

Right now, it takes about 24 hours and 1 minute for the sun to make a complete circuit in the sky, which has the effect of making it seem as if your clock is running 1 minute slow when observing sunset – which starts coming later and later.

Dec. 7 is usually the date in the US when this phenomena overtakes the effect of the sun’s southward movement and starts making sunset appear later, rather than earlier. The earliest sunrise, on the other hand comes around Jan. 6.

The tilt of the Earth is what makes the sun appear to move north and south throughout the year, but the elliptical orbit is the main factor that causes the solar day to vary in length. That’s because when the Earth is near its perihelion, or closest point to the sun, it travels in a slightly larger arc of its orbit each day than it does at aphelion – so the Earth has to rotate a bit further each day for the sun to return to high noon.

It’s hard to visualize, but if you Google “analemma” and “earliest sunset” you’ll find some good illustrations of the phenomena.